Thermoplastic resin composition

ABSTRACT

The invention provides a thermoplastic resin composition which is excellent in transparency, heat resistance, resistance to chemicals, and mechanical strength as well as moldability, printability, etc. The thermoplastic resin composition containing a polycarbonate resin in an amount of 2 to 99.5 wt. % and a polyester resin in an amount of 98 to 0.5 wt. %, wherein the polyester resin (B) contains diol units each having a cyclic acetal skeleton in an amount of 20 to 60 mol % with respect to total diol structural units.

TECHNICAL FIELD

The present invention relates to a thermoplastic resin composition,which comprises a polycarbonate resin and a polyester resin and hasexcellent transparency, heat resistance, resistance to chemicals andmechanical strength as well as moldability, printability, etc., thepolyester resin containing units derived from (hereinafter “unitsderived from” referred to simply as “unit”) a diol having a cyclicacetal skeleton in a predetermined amount with respect to total diolstructural units. The invention also relates to an injection moldedproduct, a sheet, and a film, each being produced from the thermoplasticresin composition. The present invention also relates to anotherthermoplastic resin composition, which comprises the above thermoplasticcomposition and an organic and/or inorganic filler added thereto andwhich has excellent mechanical strength, heat resistance, and resistanceto chemicals as well as moldability, printability, etc.

BACKGROUND ART

Polycarbonate resin (hereinafter may be referred to as “PC”) havingadvantages such as heat resistance, impact resistance, and transparency,has been employed in various fields such as exterior materials,electronic and electric uses, and optical disk substrates. Polycarbonateresins having such advantages have further been applied to uses such asautomobiles and medical materials. As applications expand, improvementof resistance to chemicals has been keenly demanded.

In order to improve resistance of PC to chemicals, there has beencarried out melt mixing of a saturated polyester resin serving as amodifier into PC. For example, use of polyethylene terephthalate(hereinafter may be referred to as “PET”) as a modifier for PC has beenproposed. However, addition of PET is known to considerably impairtransparency of PC. In order to solve this problem, measures currentlyundertaken include use of a method of melt mixing employing a longresidence time and a method of melt mixing employing a Ti-base catalyst.However, even when these measures are taken, obtained transparency isnot sufficient, and there arise problems of yellowing of the compositioncaused by thermal decomposition, and generation of gases such asaldehyde during decomposition. In addition, since PET has a relativelylow glass transition temperature (Tg), heat resistance of the resincomposition becomes very low, which is also problematic.

When polybutylene terephthalate resin (hereinafter may be referred to as“PBT”) is employed as a modifier for PC, a certain level of transparencyis attained. However, the transparency is not yet satisfactory, and heatresistance decreases considerably, which is also problematic. Meanwhile,there has been proposed a thermoplastic resin composition including PCand a modified PET, in which diol units are changed to1,4-cyclohexanedimethanol units (40 mol %) (Japanese Patent ApplicationLaid-Open (kokai) No. 2000-63641). However, the resin composition has adrawback of reduced heat resistance and poor resistance to chemicals,although the resin composition has good transparency.

There has also been proposed use, as a modifier for PC, of a copolymerpolyester containing a predetermined proportion ofnaphthalenedicarboxylic acid units in the dicarboxylic acid units of theresin (Japanese Patent Application Laid-Open (kokai) No. 2000-103948).However, when naphthalenedicarboxylic acid units are incorporated intothe dicarboxylic acid units in a proportion required for improvingresistance to chemicals, transparency problematically decreases to anunsatisfactory level. Thus, hitherto, there has never been known aPC-polyester resin-based composition which maintains transparency andheat resistance of PC and which has improved resistance to chemicals.

Meanwhile, as compared with PCs, polyester resins such as PET,polyethylene naphthalate, and PBT are generally excellent in resistanceto chemicals, moldability, printability, etc. but are poor in heatresistance, mechanical strength (particularly impact strength), andtransparency. Thus, improvement of such poor physical properties isdemanded.

For the purpose of improving properties of a polyester resin, such asheat resistance and impact strength, a thermoplastic resin produced byadding PC to the polyester through melt mixing has been proposed.However, as mentioned above, the thus-produced polyester resin hasconsiderably poor transparency. Thus, hitherto, there has never beenknown a thermoplastic composition which has both improved heatresistance and improved mechanical strength (particularly impactstrength) of polyester resin as well as high transparency.

As mentioned above, there has never been known a thermoplastic resincomposition which is formed of a polycarbonate resin and a polyesterresin and which has excellent transparency, heat resistance, resistanceto chemicals, and mechanical strength (particularly impact strength) aswell as moldability, printability, etc.

DISCLOSURE OF THE INVENTION

In view of the forgoing, an object of the present invention is toprovide a thermoplastic resin composition, which comprises apolycarbonate resin and a specific copolymer polyester resin and whichhas excellent transparency, heat resistance, resistance to chemicals,and mechanical strength (particularly impact strength) as well asmoldability, printability, etc. Another object of the invention is toprovide an injection molded product, a sheet, and a film, each beingproduced from the thermoplastic resin composition. Still another objectis to provide a thermoplastic resin composition, which comprises theabove thermoplastic composition and an organic and/or inorganic filleradded thereto and which has excellent mechanical strength, heatresistance, and resistance to chemicals as well as moldability,printability, etc.

The present inventors have carried out extensive studies so as to solvethe aforementioned problems, and have found that a thermoplastic resincomposition obtained through blending a polycarbonate resin with acopolymer polyester resin containing a predetermined amount of diolunits having a cyclic acetal skeleton serving as polyester diolstructural units has excellent transparency, heat resistance, resistanceto chemicals, and mechanical strength as well as moldability,printability, etc. The present invention has been accomplished on thebasis of this finding. Accordingly, the present invention is directed tothe following (1) to (5).

(1) A thermoplastic resin composition (C) comprising a polycarbonateresin (A) and a polyester resin (B), characterized in that the polyesterresin (B) contains diol units each having a cyclic acetal skeleton in anamount of 20 to 60 mol % with respect to total diol structural units,and the thermoplastic resin composition (C) contains the polycarbonateresin (A) in an amount of 2 to 99.5 wt. % and the polyester resin (B) inan amount of 98 to 0.5 wt. %.

(2) An injection molded product produced from a thermoplastic resincomposition (C) as recited in (1) above, the injection molded productexhibiting a total luminous transmittance of 87% or higher and a hazevalue of 4% or less as measured on a piece of the product having athickness of 3.2 mm.

(3) A sheet produced from a thermoplastic resin composition (C) asrecited in (1) above, the sheet exhibiting a total luminoustransmittance of 87% or higher as measured on a piece of the sheethaving a thickness of 1.0 mm.

(4) A film produced from a thermoplastic resin composition (C) asrecited in (1) above, the film exhibiting a haze value of 4% or less asmeasured on a piece of the film having a thickness of 20 μm.

(5) A thermoplastic resin composition (D) comprising a thermoplasticresin composition (C) as recited in (1) above in an amount of 100 partsby weight and, added thereto, an organic and/or inorganic filler in anamount of 1 to 100 parts by weight.

BEST MODE FOR CARRYING OUT THE INVENTION

The thermoplastic resin composition (C) of the present inventionincludes a polycarbonate resin (A) in an amount of 2 to 99.5 wt. % and apolyester resin (B) in an amount of 98 to 0.5 wt. %, the polyester resin(B) containing diol units each having a cyclic acetal skeleton in anamount of 20 to 60 mol % with respect to total diol structural units.

The polycarbonate resin (A) used in the present invention includesrepeating units represented by the following formula (1) and/or formula(2):

wherein each of R₁ and R₂ represents a hydrogen atom, a C1-C10non-cyclic hydrocarbon group, or a C5-C10 alicyclic hydrocarbon group(e.g., methyl, ethyl, propyl, n-propyl, isobutyl, pentyl, orcyclohexyl); and each of R₃ and R₄ represents a C1-C10 non-cyclichydrocarbon group, a halogen atom, or a phenyl group (e.g., methyl,ethyl, n-butyl, isobutyl, pentyl, phenyl, chlorine atom, or bromineatom); each of m and n is 0, 1, or 2; and k is 4 or 5.

No particular limitation is imposed on the aromatic hydroxy compoundforming the polycarbonate resin (A) used in the present invention, andexamples include bis(hydroxyaryl)alkanes such as2,2-bis(4-hydroxyphenyl)propane (bisphenol A),2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane (tetrabromobisphenol A),bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane,2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane,2,2-bis(4-hydroxy-3-methylphenyl)propane,1,1-bis(3-tert-butyl-4-hydroxyphenyl)propane,2,2-bis(3-bromo-4-hydroxyphenyl)propane, and2,2-bis(3,5-dichloro-4-hydroxyphenylpropane;bis(hydroxyaryl)cycloalkanes such as1,1-bis(4-hydroxyphenyl)cyclopentane,1,1-bis(4-hydroxyphenyl)cyclohexane (bisphenol Z),1,1-bis(3,5-dibromo-4-hydroxyphenyl)cyclohexane, and1,1-bis(3,5-dichloro-4-hydroxyphenyl)cyclohexane;bis(hydroxyaryl)arylalkanes such as1,1-bis(4-hydroxyphenyl)-1-phenylethane and1,1-bis(4-hydroxyphenyl)diphenylmethane; dihydroxydiaryl ethers such as4,4′-dihydroxydiphenyl ether and 4,4′-dihydroxy-3,3′-dimethyldiphenylether; dihydroxydiaryl sulfides such as 4,4′-dihydroxydiphenyl sulfideand 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfide; dihydroxydiarylsulfoxides such as 4,4′-dihydroxydiphenyl sulfoxide and4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfoxide; dihydroxydiaryl sulfonessuch as 4,4′-dihydroxydiphenyl sulfone and4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfone; hydroquinone, resorcin,and 4,4′-dihydroxydiphenyl. Of these, bisphenol A is particularlypreferred from the viewpoint of heat resistance, mechanical strength,cost, etc. of the thermoplastic resin composition (C).

The polycarbonate resin (A) of the present invention may have a branchstructure. Such aromatic polycarbonate resins having a branch structurecan be produced through use of a compound, for example, a polyhydroxycompound such as phloroglucin,2,6-dimethyl-2,4,6-tris(4-hydroxyphenyl)-3-heptene,4,6-dimethyl-2,4,6-tris(4-hydroxyphenyl)-2-heptene,1,3,5-tris(2-hydroxyphenyl)benzole, 1,1,1-tris(4-hydroxyphenyl)ethane,2,6-bis(2-hydroxy-5-methylbenzyl)-4-methylphenol, orα,α′,α″-tris(4-hydroxyphenyl)-1,3,5-triisopropylbenzene;3,3-bis(4-hydroxyaryl)oxyindole (=isatinbisphenol),5-chloroisatinbisphenol, 5,7-dichloroisatinbisphenol, or5-bromoisatinbisphenol.

The polycarbonate resin (A) used in the present invention preferably hasa viscosity average molecular weight of 10,000 or higher form theviewpoint of maintenance of mechanical strength and preferably 30,000 orless from the viewpoint of moldability. Thus, the molecular weight morepreferably falls within a range of 12,000 to 28,000, inclusive. When theviscosity average molecular weight falls within the above range, thethermoplastic resin (C) exhibits excellent mechanical strength andmoldability.

The polycarbonate resin (A) used in the present invention is produced,for example, through reaction (interface polymerization) of thecorresponding bisphenol with a carbonate precursor such as phosgene in atypical solvent such as methylene chloride in the presence of a knownacid receptor or a chain-extender, or through transesterification (meltpolymerization) of the corresponding bisphenol and a carbonate precursorsuch as diphenyl carbonate. The ratio of the amount of diol unit havinga cyclic acetal skeleton to the total amount of diol structural units inthe polyester resin (B) used in the present invention is 20 to 60 mol %,preferably 25 to 55 mol %, particularly preferably 30 to 50 mol %. Whenthe amount of diol unit having a cyclic acetal skeleton contained in thepolyester resin (B) is less than 20 mol % with respect to total diolstructural units, transparency and heat resistance of the thermoplasticresin composition (C) are not improved sufficiently, whereas the amountis in excess of 60 mol %, transparency and mechanical strength(particularly impact strength) are not improved sufficiently.

The thermoplastic resin composition (C) employing the aforementionedpolyester (B) exhibits remarkably excellent heat resistance,transparency, mechanical strength (see Examples 3, 16, 17, andComparative Examples 1 and 2).

The diol having a cyclic acetal skeleton, which serves as a part of rawmaterial monomers for producing the polyester resin (B) used in thepresent invention, is preferably a compound represented by formula (3)or (4). The diol is readily produced through reaction of any ofhydroxyaldehydes with pentaerythritol (hereinafter referred to as “PE”)or trimethylolpropane (hereinafter referred to as “TMP”) in the presenceof an acid catalyst. Examples of the diol include3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane(hereinafter referred to as “SPG”) produced from PE andhydroxypivalaldehyde (intermediate for producing neopentyl glycol,hereinafter referred to as “HPA”) and5-methylol-5-ethyl-2-(1,1-dimethyl-2-hydroxyethyl)-1,3-dioxane producedfrom HPA and TMP. By use of the polyester resin (B) produced from theabove compounds, the thermoplastic resin composition (C) of the presentinvention can provide injection molded products, sheets, films, andsimilar products having excellent transparency, heat resistance,resistance to chemicals, and mechanical strength as well as moldability,printability, etc. The compound is represented by formula (3):

wherein each of R₅ and R₆ represents a functional group selected fromamong a C1-C10 non-cyclic hydrocarbon group, a C3-C10 alicyclichydrocarbon group, and a C6-C10 aromatic hydrocarbon group, preferably amethylene group, an ethylene group, a propylene group, a butylene group,or a structural isomer thereof (e.g., an isopropylene group or anisobutylene group), or by formula (4):

wherein R₅ has the same meaning as defined above; R₇ represents afunctional group selected from among a C1-C10 non-cyclic hydrocarbongroup, a C3-C10 alicyclic hydrocarbon group, and a C6-C10 aromatichydrocarbon group, preferably a methyl group, an ethyl group, a propylgroup, a butyl group, or a structural isomer thereof (e.g., an isopropylgroup or an isobutyl group).

No particular limitation is imposed on the diol having no cyclic acetalskeleton, which serves as a raw material for producing the polyesterresin (B) used in the present invention, and examples include aliphaticdiols such as ethylene glycol, trimethylene glycol, 1,4-butanediol,1,5-pentanediol, 1,6-hexanediol, diethylene glycol, and propyleneglycol; polyether compounds such as polyethylene glycol, polypropyleneglycol, and polybutylene glycol; alicyclic diols such as1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol,1,2-decahydronaphthalenedimethanol, 1,3-decahydronaphthalenedimethanol,1,4-decahydronaphthalenedimethanol, 1,5-decahydronaphthalenedimethanol,1,6-decahydronaphthalenedimethanol, 2,7-decahydronaphthalenedimethanol,tetraline dimethanol, norbornanedimethanol, tricyclodecanedimethanol,and pentacyclododecanedimethanol; bisphenols such as4,4′-(1-methylethylidene)bisphenol, methylenebisphenol (bisphenol F),4,4′-cyclohexylidenebisphenol (bisphenol Z), and 4,4′-sulfonylbisphenol(bisphenol S); alkylene oxide adducts of bisphenol; aromatic dihydroxycompounds such as hydroquinone, resorcin, 4,4′-dihydroxybiphenyl,4,4′-dihydroxydiphenyl ether, and 4,4′-dihydroxydiphenylbenzophenone;and alkylene oxide adducts of the aromatic dihydroxy compounds. Ofthese, ethylene glycol is particularly preferred from the viewpoint ofmechanical strength and cost of the thermoplastic resin composition (C).

The polyester resin (B) used in the present invention preferablycontains units derived from ethylene glycol in an amount of 80 to 40 mol% with respect to total diol structural units, more preferably 75 to 45mol %, particularly preferably 70 to 50 mol %. When the above units arecontained in an amount falling with in the above ranges, thethermoplastic resin composition (C) exhibits remarkably excellenttransparency, mechanical strength, cost performance, etc.

The polyester resin (B) used in the present invention may furthercontain a monohydric alcohol such as butyl alcohol, hexyl alcohol, oroctyl alcohol, or a polyhydric alcohol such as trimethyrolpropane,glycerin, or pentaerythritol in such an amount that does not impede theobjects of the present invention.

No particular limitation is imposed on the dicarboxylic acid componentof the polyester resin (B) used in the present invention, and examplesinclude aliphatic dicarboxylic acids such as succinic acid, glutaricacid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacicacid, dodecanedicarboxylic acid, cyclohexanedicarboxylic acid,decanedicarboxylic acid, norbornanedicarboxylic acid,tricyclodecanedicarboxylic acid, pentacyclododecanedicarboxylic acid,3,9-bis(1,1-dimethyl-2-carboxyethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane,and 5-carboxy-5-ethyl-2-(1,1-dimethyl-2-carboxyethyl)-1,3-dioxane;ester-formable derivatives of the aliphatic dicarboxylic acids; aromaticdicarboxylic acid such as terephthalic acid, isophthalic acid, phthalicacid, 2-methylterephthalic acid, 1,4-naphthalenedicarboxylic acid,1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid,2,7-naphthalenedicarboxylic acid, biphenyldicarboxylic acid, andtetraline dicarboxylic acid; and ester-formable derivatives of thearomatic dicarboxylic acids.

Among these compounds, aromatic dicarboxylic acids and ester-formablederivatives thereof are preferred from the viewpoint of heat resistance,mechanical strength, resistance to chemicals, or other factors, withterephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid,ester-formable derivatives thereof being particularly preferred. Throughemployment of terephthalic acid or and ester-formable derivativethereof, the thermoplastic resin composition (C) exhibits remarkablyexcellent transparency and mechanical strength and is produced at lowcost, whereas through employment of 2,6-naphthalenedicarboxylic acid oran ester-formable derivative thereof, the thermoplastic resincomposition (C) exhibits remarkably excellent transparency, resistanceto chemicals, and heat resistance of the thermoplastic resin composition(C).

The ester-formable derivative of dicarboxylic acid of the presentinvention is a compound being capable of forming a dicarboxylic acidester, and example include dicarboxylic acid dialkyl esters,dicarboxylic acid dihalides, and dicarboxylic acid diamides. Of these,dicarboxylic acid dialkyl esters are preferred, with dicarboxylic aciddimethyl esters being particularly preferred.

The polyester resin (B) generally contains aromatic dicarboxylic acidunits in an amount of preferably 70 mol % or more with respect to totaldicarboxylic acid structural units, more preferably 80 mol % or more,particularly preferably 90 mol % or more. By controlling the amount ofthe aromatic dicarboxylic acid units with respect to total dicarboxylicacid structural units of the polyester resin (B) to the aforementionedranges, the thermoplastic resin composition (C) exhibits more excellentheat resistance, mechanical strength, and resistance to chemicals.

In the case where the polyester resin (B) containing aromaticdicarboxylic acid units in an amount of 70 mol % or more with respect tototal dicarboxylic acid structural units further contains terephthalicacid units in the dicarboxylic acid structural units, the amount ofterephthalic acid units in the dicarboxylic acid structural unitspreferably 20 to 100 mol %, more preferably 30 to 80 mol %, particularlypreferably 40 to 60 mol %. By controlling the amount of the terephthalicacid units with respect to total dicarboxylic acid structural units ofthe polyester resin (B) to the aforementioned ranges, the thermoplasticresin composition (C) exhibits remarkably excellent transparency andmechanical strength (Examples 1 to 3 and Comparative Examples 4 to 7).

In the case where the polyester resin (B) containing aromaticdicarboxylic acid units in an amount of 70 mol % or more with respect tototal dicarboxylic acid structural units further contains2,6-naphthalenedicarboxylic acid units in the aromatic dicarboxylic acidstructural units, the amount of 2,6-naphthalenedicarboxylic acid unitsin the dicarboxylic acid structural units preferably 5 to 80 mol %, morepreferably 20 to 70 mol %, particularly preferably 40 to 60 mol %. Bycontrolling the amount of the 2,6-naphthalenedicarboxylic acid unitswith respect to total dicarboxylic acid structural units of thepolyester resin (B) to the aforementioned ranges, the thermoplasticresin composition (C) exhibits remarkably excellent transparency, heatresistance, and resistance to chemicals (Examples 8 and 9 andComparative Examples 3 to 7).

In addition to the aforementioned aromatic dicarboxylic acid components,a polyvalent carboxylic acid compound having, in one molecule, three ormore carboxylic groups bonded to an aromatic ring may be employed as araw material monomer for the polyester resin (B). Alternatively, asimilar polyvalent carboxylic acid compound having three or morecarboxyl groups bonded to an aromatic ring, with two or more carboxylgroups forming an anhydride ring may also be employed. Examples of suchcarboxylic acid compounds include trimellitic acid, pyromellitic acid,trimellitic anhydride, naphthalenetricarboxylic anhydrixdes havingdifferent carboxylic group bonding positions on the aromatic ring,anthracenetricarboxylic acids, benzophenonetricarboxylic anhydrides,benzenetetracarboxylic monoanhydride, naphthalenetetracarboxylicdianhydrides, anthracenetetracarboxylic dianhydrides,biphenyltetracarboxylic dianhydrides, and ethylenebis(trimelliticanhydride).

The raw material monomers for the polyester resin (B) may include ahydroxy acid such as glycolic acid, lactic acid, 2-hydroxyisobutyricacid, or 3-hydroxyisobutyric acid or a monocarboxylic acid such asbenzoic acid, propionic acid, or butyric acid, in such an amount thatdoes not impede the objects of the present invention.

No particular limitation is imposed on the method for producing thepolyester resin (B) of the present invention, and any conventionallyknown method can be employed. Examples include melt polymerization suchas transesterification and direct esterification, and solutionpolymerization. No particular limitation is imposed on thetransesterification catalyst and esterification catalyst, and anyconventionally known catalysts can be used. Examples of the catalystsinclude sodium alkoxides and magnesium alkoxides; aliphatic acid salts,carbonates, phosphates, hydroxides, chlorides, and oxides of zinc, lead,cerium, cadmium, manganese, cobalt, lithium, sodium, potassium, calcium,nickel, magnesium, vanadium, aluminum, titanium, germanium, antimony, ortin; and metallic magnesium. These catalysts may be used singly or incombination of two or more species. No particular limitation is imposedon the polycondensation catalyst, and any conventionally known catalystscan be used. For example, the aforementioned catalysts can be used.These catalysts may be used singly or in combination of two or morespecies.

Upon production of the polyester resin (B), knownetherification-preventing agents, stabilizers such as a heat stabilizerand a photostablizer; polymerixation regulators may be used. Specificexamples of etherification-preventing agents include amine compounds.Addition, as a heat stabilizer, of any of a variety of phosphoruscompounds such as phosphoric acid, phosphorous acid, andphenylphosphonic acid is also effective. Other additives such as aphotostabilizer, an antistatic agent, a lubricant, an antioxidant, areleasing agent, a dye, and a pigment may also added.

The polyester (B) preferably has a glass transition temperature, asmeasured by means of a differential scanning calorimeter, of 70° C. orhigher, more preferably 80° C. or higher, particularly preferably 90° C.or higher. When the glass transition temperature of the polyester resin(B) falls within the above ranges, the thermoplastic resin composition(C) exhibits remarkably excellent heat resistance.

Upon mixing with the polycarbonate resin (A), the polyester resin (B) ispreferably dried so as to attain a water content in the resin of 300 ppmor lower, preferably 100 ppm or lower. By controlling the water contentso as to fall within the above ranges, deterioration of the polyesterresin (B) during melt kneading with the polycarbonate resin (A) can beprevented. No particular limitation is imposed on the intrinsicviscosity (as measured at 25° C., in a mixture solvent of phenol and1,1,2,2-tetrachloroethane (6/4 by mass)) of the polyester resin (B) usedin the present invention. However, the viscosity is generally 0.3 to 2.0dL/g, preferably 0.4 to 1.8 dL/g. An intrinsic viscosity of 0.3 orhigher means that the polyester resin (B) has satisfactorily highmolecular weight. Thus, molded products of the thermoplastic resincomposition (C) employing such a polyester resin exhibits remarkablyexcellent mechanical strength.

The polyester resin (B) preferably has a melt viscosity, as measured at240° C. and a shear rate of 100 s⁻¹, of 300 to 5,000 Pa·s, morepreferably 500 to 2,000 Pa·s. A melt viscosity falling within the aboveranges means that the polyester resin (B) can be well mixed with thepolycarbonate resins (A) during melt mixing. Thus, the thermoplasticresin composition (C) exhibiting excellent transparency and mechanicalstrength can be produced.

The polyester resin (B) preferably has a molecular weight distributionfactor of 2.5 to 12.0, more preferably 2.5 to 8.0. When the molecularweight distribution factor falls within the above ranges, the polyesterresin has remarkably excellent moldability suitable for molding intoproducts such as film, sheets, and thin hollow container.

As used herein, the term “molecular weight distribution factor” refersto a ratio of weight average molecular weight (Mw) to number averagemolecular weight (Mn); i.e., Mw/Mn. The molecular weight distributionfactor can be controlled by tuning the time of addition of a diol havinga cyclic acetal skeleton, molecular weight of the polyester resin (B),polymerization temperature, and type of additives.

The thermoplastic resin composition (C) of the present inventionincludes a polycarbonate resin (A) in an amount of 2.0 to 99.5 wt. %,preferably 5 to 99.0 wt. %, more preferably 10 to 95 wt. % and apolyester resin (B) in an amount of 98.0 to 0.5 wt. %, preferably 95 to1.0 wt. %, more preferably 90 to 5 wt. %, the polyester resin (B)containing diol units each having a cyclic acetal skeleton in an amountof 20 to 60 mol % with respect to total diol structural units.

When the thermoplastic resin composition (C) includes a polycarbonateresin (A) in an amount of 99.5 wt. % or less and a polyester resin (B)in an amount of 0.5 wt. % or more, resistance to chemicals of thepolycarbonate resin (A) is considerably improved, and moldability andprintability of the resin are also improved. Notably, when thethermoplastic resin composition (C) includes a polyester resin (B) in anamount of 0.3 wt. % or more, chemical resistance effect of thepolycarbonate resin (A) is provided. When the thermoplastic resincomposition (C) includes a polycarbonate resin (A) in an amount of 2.0wt. % or more and a polyester resin (B) in an amount of 98.0 wt. % orless, mechanical strength (particularly impact strength) and heatresistance of the polyester resin (B) are improved.

The thermoplastic resin composition (C) is produced by mixing componentsthrough a conventionally known method. In one exemplified procedure, apolycarbonate resin (A) and a polyester resin (B) are dry blended bymeans of a tumbler, a V-blender, a Henschel mixer, or a similarapparatus, to thereby form a mixture. The mixture is melt-mixed at leastonce by means of a single-screw extruder, a twin-screw extruder, akneader, or a similar apparatus. In accordance with need, the mixtureundergoes solid phase polymerization in high vacuum or under inert gas.

From the viewpoint of transparency, the thermoplastic resin composition(C) preferably exhibits a total luminous transmittance of 87% or higheras measured on a piece of the product having a thickness of 3.2 mm, morepreferably 88% or higher, particularly preferably 89% or higher. Thehaze value is preferably 4% or less, more preferably 3% or less,particularly preferably 2% or less.

The thermoplastic resin composition (C) preferably has a glasstransition temperature, as measured by means of a differential scanningcalorimeter, of 90° C. or higher, more preferably 110° C. or higher,particularly preferably 130° C. or higher. When the glass transitiontemperature of the thermoplastic resin composition (C) falls within theabove ranges, the thermoplastic resin composition (C) exhibitsremarkably excellent heat resistance.

From the viewpoint of impact resistance, the thermoplastic resincomposition (C) preferably has an impact strength (Izod impact strength,with notch) of 30 J/m or higher as measured on a piece of the moldedproduct having a thickness of 3.2 mm, more preferably 50 J/m or higher,particularly preferably 100 J/m or higher.

From the viewpoint of resistance to chemicals, the period of time untila crack is generated in a piece of the molded product of thethermoplastic resin composition (C) having a thickness of 3.2 mmimmersed in a solution (carbon tetrachloride (75 parts byweight)/n-butanol (25 parts by weight), 25° C.), while application of astrain (percent deformation of 1%) to the piece is maintained, ispreferably 5 seconds or longer, more preferably 7 seconds or longer,particularly preferably 10 seconds or longer.

From the viewpoint of printability, the percent cracked area of a pieceof the extruded sheet of the thermoplastic resin composition (C) havinga thickness of 1.0 mm, when the piece has been coated with a compositioncontaining an ink (13-00215 White, slow dry-type D3N25-P, product ofTeikoku Printing Inks Mfg. Co., Ltd.) and a solvent (Z-603, product ofTeikoku Printing Inks Mfg. Co., Ltd.) (ink/solvent:100/30 (wt.)) to athickness of 60 μm, dried under air blow for 10 minutes, and dried at80° C. for 10 minutes, is preferably 20% or less, more preferably 0%.

The thermoplastic resin composition (C) preferably has a melt viscosity,as measured at 240° C. and a shear rate of 100 s⁻¹, of 300 to 5,000Pa·s, more preferably 500 to 2,000 Pa·s. When the melt viscosity of thethermoplastic resin composition (C) falls within the above ranges,moldability, particularly injection moldability, extrudability, orexpansion moldability is enhanced. In addition, the molded productsobtained from the thermoplastic resin composition (C) have excellentformability in vacuum forming and pressure forming and deep drawabilityas well as secondary workability in cold bending, drilling, punching,etc.

The characteristics of the thermoplastic resin composition (C) will bedescribed in the following (I) to (III), which are categorized inaccordance with the compositional ratio of the polycarbonate resin (A)to the polyester resin (B).

(I) In the case where the thermoplastic resin composition (C) contains alarge amount of polycarbonate resin (A) and a small amount of polyesterresin (B); i.e., when the thermoplastic resin composition (C) containsthe polycarbonate resin (A) in an amount of preferably 60 to 99.5 wt. %,more preferably 70 to 95 wt. %, and the polyester resin (B) in an amountof preferably 40 to 0.5 wt. %, more preferably 30 to 5 wt. %, resistanceto chemicals, moldability, and printability of components, mainly thepolycarbonate (A), are remarkably improved without impairingtransparency, mechanical strength, and heat resistance (see Examples 1to 9, and 18 and Comparative Example 7).

Thus, the thermoplastic resin composition (C) having the aforementionedcomposition is excellent particularly in heat resistance, transparency,resistance to chemicals, and mechanical strength as well as inmoldability and printability.

Specifically, the thermoplastic resin composition (C) having theaforementioned composition has physical properties described in thefollowing (1) to (4).

(1) Heat resistance: a glass transition temperature, as measured bymeans of a differential scanning calorimeter, of 130° C. or higher.

(2) Impact resistance: an impact strength, as determined through theIzod impact test with notch, of 100 J/m or higher.

(3) Resistance to chemicals: a period of time until a crack is generatedin an injection molded piece upon immersion in a mixture solutioncontaining carbon tetrachloride in an amount of 75 parts by weight andn-butanol in an amount of 25 parts by weight, while a strain of 1% isapplied to the piece, of 5 seconds or longer.

(4) Transparency: a total luminous transmittance of 87% or higher and ahaze value of 4% or less, as measured on a molded piece having athickness of 3.2 mm.

(II) In the case where the thermoplastic resin composition (C) containscomparable amounts of polycarbonate resin (A) and polyester resin (B),i.e., when the thermoplastic resin composition (C) contains thepolycarbonate resin (A) in an amount of preferably 30 to 70 wt. %, morepreferably 40 to 60 wt. %, and the polyester resin (B) in an amount ofpreferably 70 to 30 wt. %, more preferably 60 to 40 wt. %, thepolycarbonate (A) has remarkably excellent resistance to chemicals,moldability, and printability, and the polyester resin (B) hasremarkably excellent heat resistance and mechanical strength(particularly impact strength) among others (see Examples 10 to 12 andComparative Examples 7 to 11).

Thus, the thermoplastic resin composition (C) having excellent heatresistance, mechanical strength, resistance to chemicals, moldability,and printability can be obtained without impairing transparency of thepolycarbonate resin (A) and the polyester resin (B). Specifically, thethermoplastic resin composition (C) having the aforementionedcomposition has physical properties described in the following (1) to(4).

(1) Heat resistance: a glass transition temperature, as measured bymeans of a differential scanning calorimeter, of 110° C. or higher.

(2) Impact resistance: an impact strength, as determined through theIzod impact test with notch, of 30 J/m or higher.

(3) Resistance to chemicals: a period of time until a crack is generatedin an injection molded piece upon immersion in a mixture solutioncontaining carbon tetrachloride in an amount of 75 parts by weight andn-butanol in an amount of 25 parts by weight, while a strain of 1% isapplied to the piece, of 7 seconds or longer.

(4) Transparency: a total luminous transmittance of 87% or higher and ahaze value of 4% or less, as measured on a molded piece having athickness of 3.2 mm.

(III) In the case where the thermoplastic resin composition (C) containsa small amount of polycarbonate resin (A) and a large amount ofpolyester resin (B), i.e., when the thermoplastic resin composition (C)contains the polycarbonate resin (A) in an amount of preferably 0.5 to40 wt. %, more preferably 5 to 30 wt. %, and the polyester resin (B) inan amount of preferably 99.5 to 60 wt. %, more preferably 95 to 70 wt.%, the polyester resin (B) has improved heat resistance and mechanicalstrength (particularly impact resistance) among others (see Examples 13to 17 and Comparative Examples 8 to 11).

Thus, the thermoplastic resin composition (C) having improved heatresistance and mechanical strength and excellent resistance tochemicals, moldability, and printability can be obtained withoutimpairing transparency of the polyester resin (B). Specifically, thethermoplastic resin composition (C) having the aforementionedcomposition has physical properties described in the following (1) to(4).

(1) Heat resistance: a glass transition temperature, as measured bymeans of a differential scanning calorimeter, of 90° C. or higher.

(2) Impact resistance: an impact strength, as determined through theIzod impact test with notch, of 30 J/m or higher.

(3) Resistance to chemicals: a period of time until a crack is generatedin an injection molded piece upon immersion in a mixture solutioncontaining carbon tetrachloride in an amount of 75 parts by weight andn-butanol in an amount of 25 parts by weight, while a strain of 1% isapplied to the piece, of 10 seconds or longer.

(4) Transparency: a total luminous transmittance of 87% or higher and ahaze value of 4% or less, as measured on a molded piece having athickness of 3.2 mm.

The thermoplastic resin composition (C) of the present invention mayfurther contain an additive such as a pigment, a dye, a lubricant, amatting agent, a thermal stabilizer, an anti-weathering agent, aUV-absorber, a nucleating agent, a plasticizer, a fire retardant, or anantistatic agent, so long as the effect of the present invention is notimpaired.

The thermoplastic resin composition (C) may further contain a reclaimedpolyethylene terephthalate product, a reclaimed product of modifiedpolyethylene terephthalate containing a small amount of an isophthalicacid component, a reclaimed polycarbonate product, and/or a reclaimedproduct of polyester resin and/or polycarbonate resin below standards,so long as the nature of the resin composition is not varied.

The thermoplastic resin composition (C) is suitably processed throughinjection molding, extrusion, blow molding, or expansion molding.Through such a molding process, the thermoplastic resin composition (C)is molded into a variety of products such as injection molded products,mono-layer or multi-layer sheets and molded sheets, mono-layer ormulti-layer films, heat shrinkable films, hollow containers, sheet foamproducts, beads foam products, fiber, calender-rolled products, profileextruded products, and eye glass lenses. In addition, the resincomposition can be applied to a variety of uses such as liquid paints,powder paints, toners, and adhesives. Among them, the resin compositionis particularly suitably molded into injection molded products, sheets,and films.

No particular limitation is imposed on the method for producinginjection molded products from the thermoplastic resin composition (C),and a conventionally known method can be employed. In one exemplifiedmethod, the thermoplastic resin composition (C) is fed to an injectionmolding apparatus and injected into a metallic mold of a predeterminedshape at a melting temperature of the thermoplastic resin composition(C), followed by cooling the composition in the metallic mold forsolidification, thereby producing a molded product. The injection moldedproduct obtained from the thermoplastic resin composition (C) exhibits ahaze value, as measured on a piece of the product having a thickness of3.2 mm, of 4.0% or less, preferably 3.0% or less, more preferably 2.0%or less, and exhibits a total luminous transmittance of 87% or higher,preferably 88% or higher, more preferably 89% or higher. Thus, thethermoplastic resin composition has excellent transparency. Theinjection molded product obtained from the thermoplastic resincomposition (C) preferably has a deflection temperature under load (1.82MPa), as measured on a piece of the product having a thickness of 3.2mm, of 80° C. or higher, more preferably 100° C. or higher, particularlypreferably 120° C. or higher. The thermoplastic resin composition (C)having a deflection temperature under load falling within the aboveranges has excellent heat resistance among other properties.

No particular limitation is imposed on the method for producing sheetsfrom the thermoplastic resin composition (C), and a conventionally knownmethod can be employed. For example, such sheets can be produced thoughextrusion or casting. The sheet obtained from the thermoplastic resincomposition (C) exhibits a total luminous transmittance, as measured ona piece of the sheet having a thickness of 1.0 mm, of 87% or higher,preferably 88% or higher, more preferably 89% or higher. Thus, thethermoplastic resin composition has excellent transparency. In addition,the sheet obtained from the thermoplastic resin composition (C) hasexcellent formability in vacuum forming and pressure forming and deepdrawability as well as secondary workability in cold bending, drilling,punching, etc.

No particular limitation is imposed on the method for producing filmsfrom the thermoplastic resin composition (C), and a conventionally knownmethod can be employed. Examples of the method include roll drawing,large-roll-nip drawing, and tenter drawing. The formed film throughdrawing may have shape such as flat film, tube-like shape, etc. The filmobtained from the thermoplastic resin composition (C) exhibits a hazevalue, as measured on a piece of the film having a thickness of 1.0 mm,of 4.0% or less, preferably 3.0% or less, more preferably 2.0% or less.Thus, the thermoplastic resin composition has excellent transparency.

To the thermoplastic resin composition (C) of the present invention (100parts by weight), an organic and/or inorganic filler is added in anamount of 0.1 to 150 parts by weight, preferably 1 to 130 parts byweight, more preferably 10 to 100 parts by weight, thereby producing athermoplastic resin composition (D) having excellent properties such asmechanical strength and heat resistance.

No particular limitation is imposed on the type of the organic filler,and examples include carbon fiber; fluorine-containing resins such aspolytetrafluoroethylene; ABS resins; polymethacrylate resins;polyolefins such as polyethylene and polypropylene; elastomers such aspolyolefin elastomer and polyamide elastomer; polyester resins;polyamide resins; polyurethane resins; and ionomers. No particularlimitation is imposed on the type of the inorganic filler, and examplesinclude glass fiber, glass beads, glass flakes, fibrous magnesium,potassium titanate whiskers, ceramic whiskers, talc, mica, titaniumoxide, montmorillonite, and clay (see Example 19).

The thermoplastic resin composition (D) of the present invention can besuitably processed through injection molding, extrusion, blow molding,or expansion molding. Through such a molding process, the thermoplasticresin composition of the present invention is molded into a variety ofproducts such as injection molded products, mono-layer or multi-layersheets and molded sheets, hollow containers, sheet foam products, beadsfoam products, calender-rolled products, and profile extruded products.

No particular limitation is imposed on the method for producinginjection molded products from the thermoplastic resin composition (D)of the present invention, and a conventionally known method can beemployed. In one exemplified method, the thermoplastic resin compositionis fed to an injection molding apparatus and injected into a metallicmold of a predetermined shape at a melting temperature of thethermoplastic resin composition, followed by cooling the composition inthe metallic mold, thereby producing a molded product.

EXAMPLES

The present invention will next be described in more detail by way ofExamples and Comparative Examples. The method for producing samples tobe evaluated in the Examples and Comparative Examples and the method formeasuring physical properties are as follows.

Production of Polyester Resin (B), Production Examples 1 to 13

To a polyester production apparatus (150 L) equipped with a rectifyingcolumn (packed column), a partial condenser, a total condenser, a coldtrap, agitation paddles, a heater, and a nitrogen conduit, monomers werefed in proportions shown in Table 1. To the monomers, manganese acetatetetrahydrate was added in an amount of 0.03 mol % with respect to thetotal amount of dicarboxylic acid components, and the mixture was heatedat ambient pressure under nitrogen to 200° C. so as to performtransesterifiaction. After conversion of the entire dicarboxylic acidcomponent had increased to 90 mol % or higher, 0.02 mol % (based on theentire dicarboxylic acid component) antinomy trioxide and 0.06 mol %trimethyl phosphate were added to the reaction mixture. While remainingethylene glycol was removed from the reaction system to the outsidethrough gradually elevating the temperature and reducing the pressure,polycondensation was performed at a reached temperature of 270 to 300°C. and 0.3 kPa or lower. The viscosity of the reaction product graduallyincreased, and reaction was terminated when the melt viscosity reachedan appropriate value, thereby producing the polyester resin (B) of thepresent invention.

Evaluation of Polyester Resin (B)

Polyester resins (B) were evaluated through the following procedure.Table 2 shows results of evaluation.

(1) Intrinsic Viscosity (IV)

Intrinsic viscosity of each polyester resin (B) sample was determined atconstant 25° C. by use of a mixture solvent (ratio by mass:phenol/1,1,2,2-tetrachloroethane=6/4).

(2) Molecular Weight Distribution (Mw/Mn)

Molecular weight distribution factor of each polyester resin (B) samplewas determined through gel permeation chromatography (GPC), andcalibrated with respect to polystyrene as a standard. GPC was performedby means of TOSHO 8020 (product of TOSOH Corporation, two columns of TSKGMH_(HR-L) and one column of TSK G5000_(HR) being connected, thesecolumns are also products of TOSOH Corporation) at a column temperatureof 40° C. Chloroform serving as an eluent was caused to flow at 1.0mL/min, and detection was carried out by means of a UV detector.

(3) Diol Units Having a Cyclic Acetal Skeleton Included in the EntireDiol Structural Unit of Polyester Resin

The amount of diol units having a cyclic acetal skeleton with respect tothe total diol structural units of the polyester resin was calculatedthrough ¹H-NMR measurement. The measurement was performed by use ofNM-AL 400 (product of JEOL Ltd.) at 400 MHz with heavy chloroform as asolvent.

Examples 1 to 17, Comparative Examples 1 to 6

Polycarbonate resin (A) employed was a polycarbonate resin (trade name:Iupilon S-3000, product of Mitsubishi Engineering-Plastics Corpotation,Mv: 2.3×10⁴).

(1) Production of Thermoplastic Resin Composition (C)

Polycarbonate resin (A) and polyester resin (B) were mixed by use of atumbler at a compositional proportion shown in Tables 3 to 10, therebyproduce each resin mixture. The resin mixture was melt-mixed by use of atwin-screw extruder (screw diameter: 37 mm, L/D: 42) under the followingconditions: cylinder temperature of 265° C. to 285° C., die temperature265° C. to 285° C., and screw speed of 100 rpm.

(2) Production of Injection Molded Products

Each of the thus-produced thermoplastic resin composition (C) sampleswas molded by use of a screw-type injection molding apparatus (screwdiameter: 32 mm, clamping pressure: 9.8 kN) at a cylinder temperature of260° C. to 280° C. and a metallic mold temperature of 35° C., therebyforming test pieces having a thickness of 3.2 mm.

(3) Production of Sheets

Each of the thus-produced thermoplastic resin composition (C) sampleswas molded by use of a twin-screw extruder (screw diameter: 20 mm, L/D:25) through the T-die method under the following conditions: cylindertemperature of 265° C. to 285° C., T-die temperature 265° C. to 285° C.,and screw speed of 50 rpm, thereby forming sheet samples having athickness of 1.0 mm.

(4) Production of Films

Each sheet sample having a thickness of 100 μm which had been producedunder the conditions as described in (3) above was biaxially stretched(2.2×2.2, simultaneously) at a temperature higher than the glasstransition temperature of each thermoplastic resin composition (C)sample by 10 to 20° C.

Example 18

The procedure of Example 1 was repeated, except that a polycarbonateresin (product of Mitsubishi Engineering Plastics, Mv: 2.3×10⁴) composedof the repeating unit:

serving as polycarbonate resin (A) was used.

Example 19

The procedure of Example 3 was repeated, except that polycarbonate resin(A), polyester resin (B), and glass fiber as a filler were used as rawmaterials for producing the thermoplastic resin compositions (C) inamounts shown in Table 8.

Comparative Example 7

The procedure of Example 1 was repeated, except that the production stepof each thermoplastic resin composition by use of a twin-screw extruderwas not carried out.

Comparative Examples 8 to 11

The procedure of Comparative Example 7 was repeated, except thatproduction of injection molded products was performed under thefollowing conditions: cylinder temperature of 240° C. to 280° C. and ametallic mold temperature 35° C., and that production of sheets wasperformed under the following conditions: cylinder temperature of 240°C. to 280° C., T-die temperature 240° C. to 280° C., and screw speed of50 rpm.

<Method of Evaluation>

The method of evaluating the resin compositions of Examples 1 to 19 andComparative Examples 1 to 11 is as follows. Results of the evaluationare collectively shown in Tables 3 to 11.

(1) Haze Value and Total Luminous Transmittance:

Measurement was performed on injection molded product samples(thickness: 3.2 mm), sheet samples (thickness: 1.0 mm), and film samples(thickness: 20 μm), in accordance with JIS K7105 and ASTM D1003.

The measurement apparatus employed was a haze meter (model: COH-300A,product of Nippon Denshoku Industries Co., Ltd.).

(2) Deflection Temperature Under Load

Deflection temperature was measured under a load of 1.82 MPa inaccordance with ASTM D648.

(3) Glass Transition Temperature

Glass transition temperature (Tgm) of each polyester resin was measuredby use of a DSC/TA-50WS (product of Shimadzu Corporation). A sample(about 10 mg) was placed in a non-sealed aluminum container and heatedunder nitrogen flow (30 mL/min) at an elevation rate of 20° C./min.

The temperature corresponding to the ½ value of the difference in heightof two base lines (before and after transition) drawn along the DSCcurve was regarded as the glass transition temperature.

(4) Resistance to Chemicals <1>

The period of time until a crack is generated in the surface of a testpiece (molded product) having a thickness of 3.2 mm coated with a testchemical at 25° C., while application of a strain (percent deformationof 0.5%) to the piece is maintained, was measured.

The test chemical used was dioctyl phthalate (product of Tokyo KaseiKogyo Co., Ltd.).

(5) Resistance to Chemicals <2>

The period of time until a crack is generated in a test piece (moldedproduct) having a thickness of 3.2 mm immersed in a solution (carbontetrachloride (75 parts by weight)/n-butanol (25 parts by weight), 25°C.), while application of a strain (percent deformation of 1%) to thepiece is maintained, was measured (number of runs: 5).

(6) Impact Resistance

Each test piece having a thickness of 3.2 mm was subjected to the Izodimpact test (with notch) in accordance with JIS K7110.

(7) Printability

To each sheet sample having a thickness of 1.0 mm, a mixture containingan ink (13-00215 White, slow dry-type D3N25-P, product of TeikokuPrinting Inks Mfg. Co., Ltd.) and a solvent (Z-603, product of TeikokuPrinting Inks Mfg. Co., Ltd.) (ink/solvent: 100/30 (wt.)) was applied toa thickness of 60 μm by use of an applicator. The percent cracked areaof the ink-coated portion of the sample, when the sample had been driedunder air blow for 10 minutes and further dried at 80° C. for 10 minuteswas measured (number of runs: 5).

(8) Formability

Formability of each sheet sample having a thickness of 1.0 mm duringvacuum forming or pressure forming (draw ratio: 1.5) was visuallyobserved and evaluated on the basis of the following ratings.

-   ◯: Formable to attain the shape of metallic mold-   Δ: Forming incomplete-   X: Vacuum forming or pressure forming not possible

Notably, in Tables 1 and 2, dimethyl terephthalate was abbreviated as“DMT,” dimethyl 2,6-naphthalenedicarboxylate as “NDC,”, dimethylisophthalate as “DMI,” ethylene glycol as “EG,”1,4-cyclohexanedimethanol as “CHDM,”3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro[5.5]undecanas “SPG,” 5-methylol-5-ethyl-2-(1,1-dimethyl-2-hydroxyethyl)-1,3-dioxaneas “DOG,” intrinsic viscosity as “IV,” and molecular weight distributionfactor as “Mw/Mn.” TABLE 1 Production Dicarboxylic acid Diol componentsExample components (mol) (mol) No. DMT NDC DMI EG SPG DOG CHDM Pro. Ex.1 277 — — 444 28 — — Pro. Ex. 2 249 — — 399 50 — — Pro. Ex. 3 227 — —385 68 — — Pro. Ex. 4 184 — — 360 101 — — Pro. Ex. 5 166 — — 299 116 — —Pro. Ex. 6 251 — — 427 — 75 — Pro. Ex. 7 249 — — 348 — — 149 Pro. Ex. 8204 — 23 385 68 — — Pro. Ex. 9 175 44 — 350 77 — — Pro. Ex. 10 35 141 —360 79 — — Pro. Ex. 11 312 — — 531 — — — Pro. Ex. 12 122 122 — 487 — — —Pro. Ex. 13 — 200 — 400 — — —

TABLE 2 Percent copolymerization of diol having a cyclic acetal skeletonIV Mw/Mn (mol %) Pro. Ex. 1 0.70 3.0 10 Pro. Ex. 2 0.70 3.0 20 Pro. Ex.3 0.70 3.1 30 Pro. Ex. 4 0.70 3.5 55 Pro. Ex. 5 0.66 3.5 70 Pro. Ex. 60.70 3.0 30 Pro. Ex. 7 0.70 3.0 0 Pro. Ex. 8 0.70 3.0 30 Pro. Ex. 9 0.693.1 30 Pro. Ex. 10 0.70 3.4 45 Pro. Ex. 11 0.70 2.8 0 Pro. Ex. 12 0.683.1 0 Pro. Ex. 13 0.71 2.9 0

TABLE 3 Example No. Ex. 1 Ex. 2 Ex. 3 Ex. 4 Pro. Ex. Pro. Ex. Pro. Ex.Pro. Ex. Production of polyester resin 3 3 3 3 Composition ofthermoplastic resin (wt. %) Polycarbonate resin (A) 99.5 99 95 90Polyester resin (B) 0.5 1 5 10 Evaluation results of thermoplastic resinInjection molded products Haze (%) 0.7 0.6 0.7 0.8 Total luminoustransmittance (%) 90 90 90 90 Glass transition temp. (° C.) 159 158 156153 Deflection temp. under load (° C.) 130 130 128 125 Resistance tochemicals 1 (hr) >72 >72 >72 >72 Resistance to chemicals 2 (sec) 7 9 1111 Impact resistance (J/m) >300 >300 >300 >300 Sheets Total luminoustransmittance (%) 91 91 91 91 Printability (%) 20 20 0 0 Formability ◯ ◯◯ ◯ Films Haze (%) 0.5 0.4 0.4 0.4

TABLE 4 Example No. Ex. 5 Ex. 6 Ex. 7 Ex. 8 Pro. Pro. Pro. Pro.Production of polyester resin Ex. 6 Ex. 2 Ex. 6 Ex. 9 Composition ofthermoplastic resin (wt. %) Polycarbonate resin (A) 80 99 99 99.5Polyester resin (B) 20 1 1 0.5 Evaluation results of thermoplastic resinInjection molded products Haze (%) 0.8 2.3 1.5 0.6 Total luminoustransmittance (%) 90 89 90 90 Glass transition temp. (° C.) 145 159 159159 Deflection temp. under load (° C.) 117 130 130 130 Resistance tochemicals 1 (hr) >72 >72 >72 >72 Resistance to chemicals 2 (sec) 10 6 812 Impact resistance (J/m) 100 >300 >300 >300 Sheets Total luminoustransmittance (%) 91 90 91 91 Printability (%) 0 0 0 0 Formability ◯ ◯ ◯◯ Films Haze (%) 0.6 1.4 0.9 0.4

TABLE 5 Example No. Ex. 9 Ex. 10 Ex. 11 Production of polyester resinPro. Ex. 10 Pro. Ex. 3 Pro. Ex. 3 Composition of thermoplastic resin(wt. %) Polycarbonate resin (A) 99.5 60 40 Polyester resin (B) 0.5 40 60Evaluation results of thermoplastic resin Injection molded products Haze(%) 0.7 0.7 0.8 Total luminous transmittance (%) 90 90 90 Glasstransition temp. (° C.) 159 137 125 Deflection temp. under load (° C.)130 110 101 Resistance to chemicals 1 (hr) >72 >72 >72 Resistance tochemicals 2 (sec) 15 8 9 Impact resistance (J/m) >300 45 40 Sheets Totalluminous transmittance (%) 91 91 91 Printability (%) 0 0 0 Formability ◯◯ ◯ Films Haze (%) 0.5 0.7 0.7

TABLE 6 Example No. Ex. 12 Ex. 13 Ex. 14 Production of polyester resinPro. Ex. 8 Pro. Ex. 3 Pro. Ex. 3 Composition of thermoplastic resin (wt.%) Polycarbonate resin (A) 50 20 10 Polyester resin (B) 50 80 90Evaluation results of thermoplastic resin Injection molded products Haze(%) 1.1 0.8 0.7 Total luminous transmittance (%) 89 90 90 Glasstransition temp. (° C.) 131 114 109 Deflection temp. under load (° C.)106 91 86 Resistance to chemicals 1 (hr) >72 >72 >72 Resistance tochemicals 2 (sec) 11 11 11 Impact resistance (J/m) 43 38 37 Sheets Totalluminous transmittance (%) 89 91 91 Printability (%) 0 0 0 Formability ◯◯ ◯ Films Haze (%) 0.7 0.6 0.6

TABLE 7 Example No. Ex. 15 Ex. 16 Ex. 17 Production of polyester resinPro. Ex. 3 Pro. Ex. 2 Pro. Ex. 4 Composition of thermoplastic resin (wt.%) Polycarbonate resin (A) 5 5 5 Polyester resin (B) 95 95 95 Evaluationresults of thermoplastic resin Injection molded products Haze (%) 0.71.5 1.0 Total luminous transmittance (%) 90 88 89 Glass transition temp.(° C.) 106 101 118 Deflection temp. under load (° C.) 84 78 98Resistance to chemicals 1 (hr) >72 >72 >72 Resistance to chemicals 2(sec) 12 11 13 Impact resistance (J/m) 34 35 30 Sheets Total luminoustransmittance (%) 90 89 89 Printability (%) 0 0 0 Formability ◯ ◯ ◯Films Haze (%) 0.5 1.1 0.9

TABLE 8 Example No. Ex. 18 Ex. 19 Production of polyester resin Pro. Ex.3 Pro. Ex. 3 Composition of thermoplastic resin (wt. %) Polycarbonateresin (A) 95 95 Polyester resin (B) 5 5 Filter 0 30 Evaluation resultsof thermoplastic resin Injection molded products Haze (%) 0.7 1.5 Totalluminous transmittance (%) 90 88 Glass transition temp. (° C.) 198 160Deflection temp. under load (° C.) 168 135 Resistance to chemicals 1(hr) >72 >72 Resistance to chemicals 2 (sec) 10 11 Impact resistance(J/m) >300 >300 Sheets Total luminous transmittance (%) 90 89Printability (%) 0 0 Formability ◯ Δ Films Haze (%) 0.5 1.1

TABLE 9 Example No. Comp. Ex. 1 Comp. Ex. 2 Comp. Ex. 3 Comp. Ex. 4Production of polyester resin Pro. Ex. 1 Pro. Ex. 5 Pro. Ex. 7 Pro. Ex.11 Composition of thermoplastic resin (wt. %) Polycarbonate resin (A) 9595 95 95 Polyester resin (B) 5 5 5 5 Evaluation results of thermoplasticresin Injection molded products Haze (%) 13 8 0.7 54 Total luminoustransmittance (%) 84 85 89 78 Glass transition temp. (° C.) 155 157 156155 Deflection temp. under load (° C.) 128 129 128 127 Resistance tochemicals 1 (hr) >72 >72 <24 <48 Resistance to chemicals 2 (sec) 6 9 1 1Impact resistance (J/m) >300 >300 >300 >300 Sheets Total luminoustransmittance (%) 85 86 89 79 Printability (%) 0 0 100 40 Formability ◯◯ ◯ ◯ Films Haze (%) 8 6 0.4 12

TABLE 10 Example No. Comp. Ex. 5 Comp. Ex. 6 Comp. Ex. 8 Production ofpolyester resin Pro. Ex. 12 Pro. Ex. 13 Comp. Ex. 7 Pro. Ex. 3Composition of thermoplastic resin (wt. %) Polycarbonate resin (A) 95 95100 0 Polyester resin (B) 5 5 0 100 Evaluation results of thermoplasticresin Injection molded products Haze (%) 23 61 0.7 0.7 Total luminoustransmittance (%) 85 76 90 90 Glass transition temp. (° C.) 156 158 159103 Deflection temp. under load (° C.) 128 129 130 81 Resistance tochemicals 1 (hr) <72 >72 <24 >72 Resistance to chemicals 2 (sec) 4 7 110 Impact resistance (J/m) >300 >300 >300 25 Sheets Total luminoustransmittance (%) 85 76 90 90 Printability (%) 20 0 100 0 Formability ◯◯ X ◯ Films Haze (%) 19 45 0.4 0.5

TABLE 11 Example No. Ex. 9 Ex. 10 Ex. 11 Pro. Pro. Pro. Production ofpolyester resin Ex. 11 Ex. 12 Ex. 13 Composition of thermoplastic resin(wt. %) Polycarbonate resin (A) 0 0 0 Polyester resin (B) 100 100 100Evaluation results of thermoplastic resin Injection molded products Haze(%) 2.5 0.8 1.7 Total luminous transmittance (%) 88 90 89 Glasstransition temp. (° C.) 84 104 124 Deflection temp. under load (° C.) 6878 88 Resistance to chemicals 1 (hr) <24 <72 >72 Resistance to chemicals2 (sec) 4 7 10 Impact resistance (J/m) 20 18 19 Sheets Total luminoustransmittance (%) 89 90 90 Printability (%) 20 0 0 Formability ◯ ◯ ◯Films Haze (%) 1.3 0.6 1.0

Industrial Applicability

According to the present invention, a thermoplastic resin composition,which comprises a polycarbonate resin and a polyester resin containingdiol units having a cyclic acetal skeleton in a predetermined amountwith respect to total diol structural units and which has excellenttransparency, mechanical strength, heat resistance, resistance tochemicals, moldability, and printability can be provided. The inventionalso provides an injection molded product, a sheet, and a film, eachbeing produced from the thermoplastic resin composition. The inventionfurther provides a thermoplastic resin composition, which comprises theabove thermoplastic composition and an organic and/or inorganic filleradded thereto and which has excellent mechanical strength, heatresistance, resistance to chemicals, moldability, and printability.

1. A thermoplastic resin composition (C) comprising a polycarbonate resin (A) and a polyester resin (B), characterized in that the polyester resin (B) contains diol units each having a cyclic acetal skeleton in an amount of 20 to 60 mol % with respect to total diol structural units, and the thermoplastic resin composition (C) contains the polycarbonate resin (A) in an amount of 2 to 99.5 wt. % and the polyester resin (B) in an amount of 98 to 0.5 wt. %.
 2. A thermoplastic resin composition (C) as described in claim 1, wherein the polycarbonate resin (A) includes repeating units represented by formula (1) and/or formula (2):

wherein each of R₁ and R₂ represents a hydrogen atom, a C1-C10 non-cyclic hydrocarbon group, or a C5-C10 alicyclic hydrocarbon group; and each of R₃ and R₄ represents a C1-C10 non-cyclic hydrocarbon group, a halogen atom, or a phenyl group; each of m and n is 0, 1, or 2; and k is 4 or
 5. 3. A thermoplastic resin composition (C) as described in claim 1, wherein the polycarbonate resin (A) is a bisphenol A polycarbonate ester.
 4. A thermoplastic resin composition (C) as described in claim 1, wherein the diol component having a cyclic acetal skeleton is represented by formula (3):

wherein each of R₅ and R₆ represents a functional group selected from the group consisting of a C1-C10 non-cyclic hydrocarbon group, a C3-C10 alicyclic hydrocarbon group, and a C6-C10 aromatic hydrocarbon group, or by formula (4):

wherein R₅ has the same meaning as defined above; R₇ represents a functional group selected from the group consisting of a C1-C10 non-cyclic hydrocarbon group, a C3-C10 alicyclic hydrocarbon group, and a C6-C10 aromatic hydrocarbon group.
 5. A thermoplastic resin composition (C) as described in claim 1, wherein the diol component having a cyclic acetal skeleton is 3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane or 5-methylol-5-ethyl-2-(1,1-dimethyl-2-hydroxyethyl)-1,3-dioxane.
 6. A thermoplastic resin composition (C) as described in claim 1, wherein the polyester resin (B) contains aromatic dicarboxylic acid units in an amount of 70 mol % or more with respect to total dicarboxylic acid structural units.
 7. A thermoplastic resin composition (C) as described in claim 1, wherein the polyester resin (B) contains one or more dicarboxylic acid units selected from the group consisting of a terephthalic acid unit, a 2,6-naphthalenedicarboxylic acid unit, and an isophthalic acid unit in dicarboxylic acid structural units.
 8. A thermoplastic resin composition (C) as described in claim 1, which has the following physical properties of (1) to (4): (1) a glass transition temperature, as measured by means of a differential scanning calorimeter, of 90° C. or higher; (2) an impact strength, as determined through the Izod impact test with notch, of 30 J/m or higher; (3) a period of time until a crack is generated in an injection molded piece upon immersion in a mixture solution containing carbon tetrachloride in an amount of 75 parts by weight and n-butanol in an amount of 25 parts by weight at 25° C., while a strain of 1% is applied to the piece, of 5 seconds or longer; and (4) a total luminous transmittance of 87% or higher and a haze value of 4% or less, as measured on a molded piece having a thickness of 3.2 mm.
 9. A thermoplastic resin composition (C) as described in claim 8, which has the following physical properties of (1) and (2): (1) a glass transition temperature, as measured by means of a differential scanning calorimeter, of 130° C. or higher; and (2) an impact strength, as determined through the Izod impact test with notch, of 100 J/m or higher.
 10. A thermoplastic resin composition (C) as described in claim 8, which has the following physical properties of (1) and (2): (1) a glass transition temperature, as measured by means of a differential scanning calorimeter, of 110° C. or higher; and (2) a period of time until a crack is generated in an injection molded piece upon immersion in a mixture solution containing carbon tetrachloride in an amount of 75 parts by weight and n-butanol in an amount of 25 parts by weight, while a strain of 1% is applied to the piece, of 7 seconds or longer.
 11. A thermoplastic resin composition (C) as described in claim 8, which has a period of time until a crack is generated in an injection molded piece upon immersion in a mixture solution containing carbon tetrachloride in an amount of 75 parts by weight and n-butanol in an amount of 25 parts by weight at 25° C., while a strain of 1% is applied to the piece, of 10 seconds or longer.
 12. An injection molded product produced from a thermoplastic resin composition (C) as recited in claim 1, the injection molded product exhibiting a total luminous transmittance of 87% or higher and a haze value of 4% or less as measured on a piece of the product having a thickness of 3.2 mm.
 13. A sheet produced from a thermoplastic resin composition (C) as recited in claim 1, the sheet exhibiting a total luminous transmittance of 87% or higher as measured on a piece of the sheet having a thickness of 1.0 mm.
 14. A film produced from a thermoplastic resin composition (C) as recited in claim 1, the film exhibiting a haze value of 4% or less as measured on a piece of the film having a thickness of 20 μm.
 15. A thermoplastic resin composition (D) comprising a thermoplastic resin composition (C) as recited in claim 1 in an amount of 100 parts by weight and, added thereto, an organic and/or inorganic filler in an amount of 1 to 100 parts by weight.
 16. A thermoplastic resin composition (C) as described in claim 2, wherein the polycarbonate resin (A) is a bisphenol A polycarbonate ester.
 17. A thermoplastic resin composition (C) as described in claim 16, wherein the diol component having a cyclic acetal skeleton is represented by formula (3):

wherein each of R₅ and R₆ represents a functional group selected from the group consisting of a C1-C10 non-cyclic hydrocarbon group, a C3-C10 alicyclic hydrocarbon group, and a C6-C10 aromatic hydrocarbon group, or by formula (4):

wherein R₅ has the same meaning as defined above; R₇ represents a functional group selected from the group consisting of a C1-C10 non-cyclic hydrocarbon group, a C3-C10 alicyclic hydrocarbon group, and a C6-C10 aromatic hydrocarbon group.
 18. A thermoplastic resin composition (C) as described in claim 17, wherein the diol component having a cyclic acetal skeleton is 3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane or 5-methylol-5-ethyl-2-(1,1-dimethyl-2-hydroxyethyl)-1,3-dioxane.
 19. A thermoplastic resin composition (C) as described in claim 18, wherein the polyester resin (B) contains aromatic dicarboxylic acid units in an amount of 70 mol % or more with respect to total dicarboxylic acid structural units.
 20. A thermoplastic resin composition (C) as described in claim 19, wherein the polyester resin (B) contains one or more dicarboxylic acid units selected from the group consisting of a terephthalic acid unit, a 2,6-naphthalenedicarboxylic acid unit, and an isophthalic acid unit in dicarboxylic acid structural units.
 21. A thermoplastic resin composition (C) as described in claim 20, which has the following physical properties of (1) to (4): (1) a glass transition temperature, as measured by means of a differential scanning calorimeter, of 90° C. or higher; (2) an impact strength, as determined through the Izod impact test with notch, of 30 J/m or higher; (3) a period of time until a crack is generated in an injection molded piece upon immersion in a mixture solution containing carbon tetrachloride in an amount of 75 parts by weight and n-butanol in an amount of 25 parts by weight at 25° C., while a strain of 1% is applied to the piece, of 5 seconds or longer; and (4) a total luminous transmittance of 87% or higher and a haze value of 4% or less, as measured on a molded piece having a thickness of 3.2 mm.
 22. A thermoplastic resin composition (C) as described in claim 21, which has the following physical properties of (1) and (2): (1) a glass transition temperature, as measured by means of a differential scanning calorimeter, of 130° C. or higher; and (2) an impact strength, as determined through the Izod impact test with notch, of 100 J/m or higher.
 23. A thermoplastic resin composition (C) as described in claim 21, which has the following physical properties of (1) and (2): (1) a glass transition temperature, as measured by means of a differential scanning calorimeter, of 110° C. or higher; and (2) a period of time until a crack is generated in an injection molded piece upon immersion in a mixture solution containing carbon tetrachloride in an amount of 75 parts by weight and n-butanol in an amount of 25 parts by weight, while a strain of 1% is applied to the piece, of 7 seconds or longer.
 24. A thermoplastic resin composition (C) as described in claim 21, which has a period of time until a crack is generated in an injection molded piece upon immersion in a mixture solution containing carbon tetrachloride in an amount of 75 parts by weight and n-butanol in an amount of 25 parts by weight at 25° C., while a strain of 1% is applied to the piece, of 10 seconds or longer.
 25. An injection molded product produced from a thermoplastic resin composition (C) as recited in claim 24, the injection molded product exhibiting a total luminous transmittance of 87% or higher and a haze value of 4% or less as measured on a piece of the product having a thickness of 3.2 mm.
 26. A sheet produced from a thermoplastic resin composition (C) as recited in claim 24, the sheet exhibiting a total luminous transmittance of 87% or higher as measured on a piece of the sheet having a thickness of 1.0 mm.
 27. A film produced from a thermoplastic resin composition (C) as recited in claim 24, the film exhibiting a haze value of 4% or less as measured on a piece of the film having a thickness of 20 μm. 